Leveling instrument



`lune 16, 1931.

Patented June V16,:'1931 UNITEDqsTArES 'i PATENT fol-Flclefg-,j

ADOLPH LANGSNER, or cHIoAGd-ILLrNoIs, iiyssreN'oR` To'EUrGENE :DIETZGEN coitoV PANY; oncnIoneo, ILLINOIS, A colmoaivrIoNk or 'DELAWARE LEVELING 'INSTRUMENT My invention relatesiito leveling. instruments and particularly to leveling instruments of the hand orpocket type.; fj c c g tancesbetween the sighted surface portions An object of mypresent invention is t provide a hand ylevelfofconvenient size, and

durable constructionj'which willfserve not only to fmeasure elevationsand depressions, but also to determinethe linear distanceo'f these points ofelevation and depression from a given sighting point. f f

vide a telescopic level ofthe hand vor pocket type to accurately determine elevations and depressions, Which isz equipped with stadia lines vforiacgcurately. determining linear dis-y tancesV simultaneously with the -level read-f inofs.vk

` further object of my invention is to provide an improved typeof spirit level forL de-V termining the relative heiglitsof twopoints,

which is provided withstadia lines adapted to be used in reading elevation points on a graduated leveling stati for the purpose of accurately indicating the distance of the leveling stati from theins'trument.- v .Y

Itis still a further obgect of my presentin-- vention to provide a telescopic hand'level of thespirit type whichgisprovided Wjitha` fo, cusing means adapted to'loezclampedina Y fixed position with'respect to stadialineswithg,

stadia lines to the eyeof the user, and when the instrument issighted upon a 'given object, such as a graduatedleveling staff, these stadia lines serve to accurately determine -the-k lineal distance ofthe object from the; user simultaneously with a determination fof the. e elevation of the object witlirespecty tothet point from Whichvthe readings-are read."y In instances for example Where ground.' is

to be leveled within ,a` given radius, it would be advantageousto determine-therelative ele-4 f vation of variousl surface portions ofthe; ground with respect to a ,common point with; i

Another objectof my inventionjisto proj in ,orf adjacent said radius,y and to alsofdeternine contemporaneously with the determina` tion of the relativefelevation, thelineal dis;

and thefpoint common thereto. My invenfV tion contemplates the provision of a leveling instrumentrwhich may beconveniently carriedinthe users pocket and which maybe employed in instancessiinilar to the example suggested to determine the elevation of points scattered` overthe radius or ground area and to determinethe distancefof each of these points from thepoint where the readingsai'e talrenvwith the instrument. e Y e y These and numerousfother objects will be apparent from. the following [detailed description when considered in yconnection with the accompanying drawings wherein:

YFigure -ldiscloses at plan view of a tele,- scopic rhand level which embodies features of my invention. j y

Figure-2 is a longitudinal sectional viewV takeii'on lne2-2of Figure l, Y

Figure 3f is;r a sectional viewrtaken transversely .of the instrument on the line 3-3 of Figure 2, c f

i Figure 4 isa similarY transverse sectionallf view taken on the line' fir-4 oi'Figure2.r e ,liligurer 5y is; a tiansversefsectional view takenon ,thelin'e 5 -5fof Figure 2. Y

Figure Gais av sectionalviewsimilar to Fig?V ure k5 and discloses analternative `or modiiedclamping arrangement, and, l,Figure 7 is a detail'view of the longitudi-V nally slidablexy bracket detached from f the level'proper. Vf

r'Referring 'now' like numerals have been employed to designate similar parts `throughout the various' iigures, one embodiment` 'of my invention resides inga leveling instrument which includes a" tubular casing 2 which telescopicallyfre-fl ceive's' a tubular kmember 4 at one end thereof.

VThef'opposite extremity of the casingfQ is closedby a suitable lens 6, which i'ssecured' lin ,position by a clamping ring 8. YAn upper portionyofthe ,casing y2, Figure 2, is formed, with anelongated aperture Vl() .and positioned y'immediately above this aperture isa spirit f to' the drawings `wherein icq in the bracket 18 are three parallel wires` 24, Figure 7, and these wires will hereinafter y be referred to as stadia Wires or lines.

` casing inthe manner just described in con-V Positioned immediately beneath the vial 12, and suitably mounted within the casing 2, isl a prism 26 and it is to be understoodthat this' prism serves to horizontally rede/ctrv an imageof the three stadia wires 24 to the eye of auser which is normally positioned adjacent a small aperture 28 within a'clamping ring 30.A The clamping ring 30 is threaded upon the' end' ofthe tubular member 4y and secures a lens' 32 in position. The opposite extremity of, the tubular member 4 carries another magnifying lens 34 which is interposed between'thelens4 and the prism 26. By moving the tubular member 4 with rre'- spect'to the casing 2, the image'of the three stadia wires may be focused, and to positively secure the member 4in position with respect to the casing 2 after the instrument has been properly focused I provide a conveniently operable clampingy ring 36. It will be'noted that' the extremity vof the'casingl 2 which receivesthe clamping ring 36 is provided with four equally spaced slots 38 and these slots 38 render the extremity of the casing suiiiciently resilient 'to permit the clamping thereof again'stthe outer surface of the tubular casing 4; This clamping action is accomplished by partially rotating the ring 36, and by referring to Figure 5 it will be seen that thisv ring cooperates' with4 a roller 40y and a cam surface 42 to'effectively clamp the quadrant portions' ofthe casing 2 extending between the slots 38 against the surface of the tubular member 4. Graduations are pro-l vided on the surface of the tubular member 4; Figure 1,r to facilitate the proper longitu- K dinal positioning of the member 4 with re.

spect to the casing. A modified form of clamping rin'g44 is disclosed in Figure 6, and it will be observed that this clamping ring 44 is rendered effective through the agency 'of ya thumb screw 46. The turning ofy the thumb screw 46 operates yto compress the nection with the operationy of the clamping ring 3 6 yto secure' the tubular member 4 in proper position. To prevent relative rotation between the'tubular member 4 and the casing 2 I provide va screw 48, Figures 2 and 6', which extendsthrough a longitudinal slot llwithin the member 4. The member 4 is tlus held aga'instrotation but may be moved longitudinally within the limits determined by the length of the slot 50.

It will be noted that the magnifying lens 34 and the prism 26 occupy substantially half of the cross sectional area of the tubular member 4 and the casing 2 respectively, as clearly shown inFigures 3 and 5. Thus when an observer looks through the opening 28 of thev instrument `and sights a distant object,

half of the cross sectional arealwithin the instrument to the' right thereof, Figures 3 and 5, will present a clear unobstructed vision of the object through the lenses 32 and 6; The other half of the cross sectional area will present to the observer an image of the three transverse stadia wires' 24, the lens' 34 in this instance serving tomagnify these stadia wires or lines; As already described, in order to bringr theimage of these lines'into focus" it is only necessary to apply a releasing movement to the clamping ring 36'and then longitudinally adjust the position of the tubular member 4 within the sleeve 2; Vhen,

the instrument occupies'a level'postion, it will be understood that the bubble 52 within the vial 12 will occupy a"central'positionwith respecttoan indicator line 53 suitably etched across the upper surface of the vial. The

reflected image of the bubble as viewed by the' observer throu 'h the agency of the prism 26 should be centra ly positioned with respect to the three stadia lines 24. That is to say,l

the middle line 24'sh`ould be seen as passing transversely of the medial portion of the bubble image. If it is *foundv lafter the instrument yhas been horizontally positioned that the image of the stadia lines'24 is notv centrally positioned with respect to said bubbles, a slight adjustment of the screw 22 will serve to adjust the bracket 18 which carries these lines, and thereby properly position said lines with respect to the level or true horizontal position' of the instrument.y At

thisfpoint ofthe description it is to be understood that the stadia lines 24are spaced so that when theimages thereof are viewed by the observer as av reading is' being taken upon a conventional graduated4 levelrod'or staiil (not shown), the distance or number of graduations which vappear to the observer as being included between the two outermost lines'24 willbe proportional tothe lineal distance between the observer and the position of the leveling rod'. For example it has been found practicalk in certain instances'v to arrange the stadia lines 24 in such a manner that when the observer sights the graduatedI scale of a leveling rod placed at a distance of 2() feet from the instrument, the space'between the outer, or in'y other words the upper and lower imagesr ofthe stadia lines will embrace a' distance or length'of'one foot upon theV leveling rod. Under such circumstances it will be apparent thatl the distance between the center line and either ofthe outer lines Y to the point from which the observations areA 'n' ou rod stands, it will obviously indicate a depres-v of the image within the prism will embrace or include a distance on the leveling rod of six inches. Obviously ifthe leveling rod is located at a distance 40 feet from such an `instrument, the number of graduations or portion of the leveling rod included between the images of the outer stadia vlines 24 will be twice as ygreat as the distance embraced by said lines when the leveling rod is positioned at a distance of 2O feetfrom the instrument.y Although in the present illustrated embodiment of my invention I havemerely indicated three stadia lines having a predeterthat any desired number of stadia lines may be employed which are arranged in various spaced relations to meet theparticular needs for which the instrument is to be used.`

To obtain a clear understanding Vof the practical Vapplicationand use of my inven` tion, assume that a certain plot of ground is to be leveledl and that it isdesirable to stake out or plot various portions of the ground area to determine how much soil should be filled in or leveled oli". In such instancesvit is only necessary for the user of my improved leveling instrumentrto select a certain location and then make a plurality of successive observations or readings upon a conventional leveling rod positioned at the points where it is desired to determineelevations with respect made. Assume for example that the eye Vof the observer is positioned feet above the ground portion at the point where the observer stands, and that it is desired to take readings at distances,'as for example, V20 or 30 feet from the observer. lVhen the images of the stadia lines 24 within the instrumentV embrace a distance on the graduated scale, held by the assistant, which is equivalent to one foot, the observer is apprised of the fact that the leveling rod is now-positioned exactly 20 feet from theY instrument.y The instrument is leveled by adjusting the instrument so as to bring the image of the middle stadia line Vmedially of the image of the bubf ble 52. It the graduation sighted upon the leveling rod whenV the instrument is thus leveled is found to be more than tive feet above the ground portion upon which the leveling sion in the ground, and likewise if Vthe distance read upon the graduated leveling rod is yless than 5 feet kit will indicate that the portion of the ground is elevated with respect to the level of the ground upon which theobserver stands..k From the foregoing description of the practical application of my invention it will be understood the inventionV contemplates the provision of a conveniently constructed hand level which may be used for determining the relative heights between two points, and also provides means whereby lineal distances may be determined contemthe tubular member 4: in lixed position wit respect to the casing 2 when the instrument has been brought into focus with the eye of the observer so that the superimposed images of the bubble 52 and the stadia lines 24: are

y clear and distinct, said focus will not be dismined spaced relation, it is to be understoodvk turbed as the instrument is carried about from place to place and subjected to the wear incident to the use of such instruments.

Although I have illustrated a leveling instrument embodying features of my invention which has a particular or predetermined arrangement and spacing of the stadia lines and a particular type of prism, it is to be understood that my invention is capable of other modifications without departing from thev scope thereof. v

Having thus described my invention what I claim as new and desire to secure by Letters Patent is A hand level of the class described including a` tubular casing, a second casing telescopically arranged within theyrst casing, manually operable means for pressing the irst casing into engagementwith the peripheral surface of the second casing for secur ing said parts in various positions of adjustment, a lensmounted at one extremity of the irst mentioned casing, a second lens spaced from the first mentioned lens and movable with the second casing, an angularly disposed relector positioned between said lenses, said first mentioned casing having an aperture positioned immediately above said reflector, an apertured 'frame positioned above said aperture, a plurality of stadia Wires arranged in predetermined spaced relation and extending across thev aperture of said frame, a housing detachably mounted upon the upper surface of said first tubular casing, a

.single screw extending through yone extremityof said housing and providing the sole adjustable support for saidapertured frame,

aspirit level vial mounted in a xed position within said housing immediately abovethe scribed lmy name. l

ADOLPH LANGSNER.y

sok 

